Shoe upper and shoe

ABSTRACT

Provided are a shoe upper and a shoe that have good fittability to the instep side of a foot and are capable of inhibiting the depression of the heal at the time of coming into contact with the ground. The present invention relates to, in one or more embodiments, a shoe upper, and the upper includes an instep cover for covering an instep side of the foot, the instep cover has a structure in which a tongue portion and an instep cover main body are formed as a single body, and a center portion of the instep cover in a width direction is substantially unstretchable in a length direction of the foot. The present invention relates to a shoe in which the shoe upper is integrated with a sole.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a shoe upper and a shoe, andspecifically to a shoe upper and a shoe that have good fittability tothe instep side and are capable of inhibiting the depression of the heelat the time of coming into contact with the ground.

2. Description of Related Art

With an upper of a sports shoe, usually, an upper main body and a tongueportion are separated from each other, and the upper covers an instepportion in a state in which the materials thereof overlap each other. Inrecent years, uppers for integrally covering the instep side have beenproposed in order to improve contact with a foot. JP 2014-210179Adiscloses a shoe upper that is produced as a one-piece knitwear andincludes a first partial region and a second partial region that havedifferent elasticities, in which the first partial region and the secondpartial region extend in directions that are basically orthogonal to alongitudinal axis, for example. JP 2014-131772A discloses an upper thatincludes a knitting element formed from at least one yarn that ismechanically manipulated in a knitting process, has a region having afirst layer and a second layer that is at least partially coextensivewith the first layer, and is formed by a one-piece construction in aprocess for flat knitting the first layer and the second layer, thesecond layer being knitted seamlessly with the first layer in the flatknitting process on two sides of the second layer.

On the other hand, in recent years, a forefoot strike for the forefootportion of a foot to land on the ground, and a midfoot strike for themidfoot portion thereof to land on the ground are the main strikes usedwhen running fast over long distances. Although these strikes have theadvantages of being unlikely to strain the knees and enabling a runnerto run efficiently and fast, it is not easy for beginner runners tolearn these strikes because a certain minimum level of skill isrequired.

JP 2014-210179A and JP 2014-131772A are examples of related art.

SUMMARY OF THE INVENTION

In the forefoot strike or the midfoot strike, the foot strikes theground first with the forefoot portion or the midfoot portion, and thenthe heel is depressed, which means the center of gravity temporarilymoves back to the heel side. Subsequently, the foot toes off the ground.The inventor of the present application found that when the depressionof the heel after the forefoot portion or the midfoot portion contactedthe ground was prevented by inhibiting the stretch of center portions ofshoe uppers in the length direction of the foot, the above phase fromfoot strike to toe off became shorter, and thus the forefoot strike orthe midfoot strike could be easily achieved.

In the case of the shoe upper disclosed in JP 2014-210179A, althoughfittability to a foot with various sizes can be flexibly exerted due tothe first partial region and the second partial region that havedifferent elasticities being provided, it is not possible to inhibit theheel from being depressed after the forefoot portion or the midfootportion has come into contact with the ground because the upperexcessively stretches in the length direction of the foot. With the shoeupper disclosed in JP 2014-131772A, flat knitting is highly stretchable,and thus the upper is likely to stretch in the length direction of thefoot, and it is not possible to inhibit the heel from being depressedafter the forefoot portion or the midfoot portion comes into contactwith the ground.

In order to resolve the above-described issues, the present inventionprovides a shoe upper and a shoe that have good fittability to theinstep side and are capable of inhibiting the heel from being depressedat the time of coming into contact with the ground.

In one or more embodiments, the present invention relates to a shoeupper, the upper including an instep cover for covering an instep sideof a foot, in which the instep cover has a structure in which a tongueportion and an instep cover main body are formed as a single body, and acenter portion of the instep cover located in a width direction issubstantially unstretchable in a length direction of the foot.

In one or more embodiments, the present invention relates to a shoe, theshoe including the shoe upper and a sole, in which the shoe upper isintegrated with the sole.

According to one or more embodiments of the present invention, it ispossible to provide a shoe upper that has good fittability to the instepside of a foot and inhibits the heel from being depressed at the time ofcoming into contact with the ground by forming the tongue portion andthe instep cover main body as a single body (bootee structure), andpreventing the center portion of the instep cover located in the widthdirection from stretching in the length direction of the foot in theinstep cover. According to one or more embodiments of the presentinvention, it is possible to provide a shoe that has good fittability tothe instep side of a foot and inhibits the heel from being depressed atthe time of coming into contact with the ground by forming the tongueportion and the instep cover main body as a single body (booteestructure), and preventing the center portion of the instep cover fromstretching in the length direction of the foot in the instep cover.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic spread-out surface view of an upper (of a leftshoe) of one or more embodiments of the present invention.

FIG. 2 is a schematic surface view of a shoe (a left shoe) of one ormore embodiments of the present invention.

FIG. 3 is a schematic back view of an upper (of a left shoe) of one ormore embodiments of the present invention.

FIG. 4 is a schematic perspective view of a shoe (a left shoe) of one ormore embodiments of the present invention.

FIG. 5 is a schematic surface view of a shoe (a left shoe) of one ormore embodiments of the present invention.

FIG. 6 is a schematic spread-out surface view of an upper (of a leftshoe) of one or more embodiments of the present invention.

FIG. 7 is a schematic spread-out surface view of an upper (of a leftshoe) of one or more embodiments of the present invention.

FIG. 8 is a schematic surface view of a shoe (a left shoe) of one ormore embodiments of the present invention.

FIG. 9 is a schematic diagram illustrating a sole used in a shoe (a leftshoe) of one or more embodiments of the present invention.

FIG. 10 is a schematic diagram illustrating the state of a shoe (a rightshoe) of one or more embodiments of the present invention worn duringrunning, showing movements of the shoe with respect to the road surfaceover time in the order of (a) to (d).

FIG. 11 is a schematic diagram illustrating the state of a right footwhen the metatarsophalangeal joint (MP joint) is flexed and extended,(a) illustrating the state of the foot when the MP joint is flexed, and(b) illustrating the state of the foot when the MP joint is extended.

DETAILED DESCRIPTION OF THE INVENTION

The inventor of the present application conducted studies regardingsupporting of the forefoot strike or the midfoot strike of runners,including beginner runners who have low forefoot or midfoot strikeskills, by improving the structure of a shoe upper. In the forefootstrike or the midfoot strike, the foot strikes the ground first with theforefoot portion or the midfoot portion, and then the heel is depressed,which means the center of gravity temporarily moves back to the heelside.

Subsequently, the foot toes off the ground. In view of this, theinventor found that the phase from foot strike (in which the forefootportion or the midfoot portion contacted the ground) to toe off can bereduced by inhibiting the center portion of an instep cover of a shoelocated in the width direction from stretching in the length directionof the foot. Thus, the forefoot strike or the midfoot strike can beeasily realized. Also, as a result of the tongue portion and the instepcover main body of the instep cover being formed as a single body (whichis so-called bootee structure), the fittability of a shoe to the instepside of a foot is improved, and a comfortable feeling can be realizedeven when the shoe is worn for a long period of time.

In one or more embodiments of the present invention, “the center portionof the instep cover located in the width direction is substantiallyunstretchable in the length direction of the foot” means that thetensile strength of the center portion of the instep cover located inthe width direction when stretched by 10% in the length direction of thefoot is 50 N/mm² or more. In one or more embodiments of the presentinvention, the center portion of the instep cover located in the widthdirection means the portion extending 20 mm left and right from thecenter line of the instep cover in the width direction, i.e., theportion having a width of 40 mm in total. In one or more embodiments ofthe present invention, the tensile strength of the center portion of theinstep cover located in the width direction when stretched by 10% in thelength direction of the foot can be measured under the followingconditions.

Test piece: a test piece extending over the entire length of an instepcover in the length direction of the foot is cut out from the instepcover such that the test piece has a width of 20 mm in the left andright directions centered on the center line in the width direction ofthe instep cover, that is, the width thereof being 40 mm in total.

Distance between chucks: the distance is set from the first eyelet tothe toe box of the unloaded test piece.

The length of the unloaded test piece is measured by cutting the testpiece, placing the cut test piece, and making the center portion thereofflat.

Tensile speed: 100 mm/min

Measurement conditions: tensile strength is measured when the test pieceis stretched by 10% of the length of the unloaded test piece.

FIG. 11 is a schematic diagram illustrating the state of a foot when theMP joint is flexed and extended, FIG. 11(a) showing a schematic diagramillustrating the state of the foot when the MP joint is flexed, and FIG.11(b) showing a schematic diagram illustrating the state of the footwhen the MP joint is extended. With regard to four healthy males aged 22to 29 and one healthy female aged 26, a length Lb from the tip of a toeto the ankle thereof when the MP joint is flexed, and a length Le fromthe tip of the toe to the ankle thereof when the MP joint is extendedwere measured, and a deformation ratio (Le−Lb)/Lb×100%) of the footassociated with the flexion and extension of the MP joint was examinedbased on the averages thereof, revealing that the length thereof changedby about 10%. In the present invention, as a result of the centerportion of the instep cover located in the width direction being keptfrom stretching in the length direction of the foot, that is, thetensile strength of the center portion of the instep cover located inthe width direction when stretched by 10% in the length direction of thefoot being 50 N/mm² or more, lifting effects are obtained, and thedepression of the heel after the forefoot portion or the midfoot portionhas come into contact with the ground during running is inhibited,making the foot being likely to move forward.

In one or more preferred embodiments of the present invention, from theviewpoint of effectively preventing the depression of the heel after theforefoot portion or the midfoot portion has come into contact with theground, the tensile strength of the center portion of the instep coverlocated in the width direction when stretched by 10% in the foot lengthdirection is preferably 55 N/mm² or more, more preferably 60 N/mm² ormore, and even more preferably 65 N/mm² or more. In one or moreembodiments of the present invention, although not particularly limited,from the viewpoint of achieving a good balance between lifting effectsand fittability to the foot, the tensile strength of the center portionof the instep cover located in the width direction when stretched by 10%in the foot length direction is preferably 80 N/mm² or less, morepreferably 70 N/mm² or less.

In one or more embodiments of the present invention, although notparticularly limited, from the viewpoint of improving wearability whenthe instep cover is worn for a long period of time, the instep cover ispreferably stretchable in the width direction of the foot, for example.The “instep cover is stretchable in the width direction of the foot”means that the tensile strength of the instep cover when stretched by10% in the width direction of the foot is 10 N/mm² or less, and thetensile strength is preferably 5 N/mm² or less, and more preferably 1N/mm² or less. In one or more embodiments of the present invention,although not particularly limited, from the viewpoint of achieving agood balance between fittability to the foot and holding properties ofthe shoe, the tensile strength of the instep cover when stretched by 10%in the width direction of the foot is preferably 0.02 N/mm² or more,more preferably 0.15 N/mm² or more. The tensile strength of the instepcover when stretched by 10% in the width direction of the foot can bemeasured in conformity with JIS L 1096.

In one or more embodiments of the present invention, the tongue portionand the instep cover main body are formed as a single body. Thisimproves contact with and fittability to the foot, and long-termwearability. In one or more embodiments of the present invention, thestructure in which “the tongue portion and the instep cover main bodyare formed as a single body” means that the tongue portion is notseparable from the instep cover main body. For example, the tongueportion and the instep cover main body may be formed as a unitarystructure from a single fabric. Alternatively, the tongue portion andthe instep cover main body may be composed of different materials, andmultiple materials may be joined together to form a unitary structure insuch a manner that the tongue portion is not separable from the instepcover main body. When the tongue portion and the instep cover main bodyare composed of different materials, both end portions of the tongueportion in the width direction of the foot are joined to the instepcover main body by, e.g., sewing, bonding, or embroidery. Thus, thedifferent materials can be joined together so that the tongue portion isnot separable from the instep cover main body. From the viewpoint ofweight reduction and air permeability, the main body and the tongueportion of the instep cover may be formed using a mesh fabric. There isno particular limitation on the mesh fabric, and it is possible to usewarp knitted fabrics such as single raschel fabrics, double raschelfabrics, and tricot, and weft knitted fabrics such as plain knittedfabrics and circular knitted fabrics as a mesh fabric. It is possible touse elastic yarns and non-elastic yarns in combination as appropriate torealize the above-described predetermined tensile strength.

In one or more embodiments of the present invention, although notparticularly limited, the elastic yarn preferably has a breakingelongation of 20% or more, and more preferably has a breaking elongationof 20% to 50%, for example. In one or more embodiments of the presentinvention, although not particularly limited, examples of the elasticyarn include elastic yarns constituted by polyurethane-based elasticfibers (also referred to as spandex), polyetherester-based elasticfibers, and nylon fibers. An elastic yarn may be constituted by elasticfibers, or may be a yarn obtained by combining elastic fibers withnon-elastic fibers, which will be described later.

In one or more embodiments of the present invention, although notparticularly limited, the non-elastic yarn preferably has a breakingelongation of less than 20%, for example. There is no particularlimitation on the non-elastic yarn, and examples thereof includenon-elastic yarns constituted by non-elastic fibers such aspolyester-based fibers such as polyethylene terephthalate andpolytrimethylene terephthalate fibers; polyamide-based fibers;polyolefin-based fibers such as polypropylene fibers; cellulosic fiberssuch as cuprammonium rayon, rayon, cotton, and bamboo fibers; and animalhair-based fibers such as wool.

In one or more embodiments of the present invention, in light of thefact that it is possible to easily realize a structure in which theinstep cover is stretchable in the width direction of the foot and thecenter portion of the instep cover located in the width direction issubstantially unstretchable in the length direction of the foot, thetongue portion is preferably constituted by a warp knitted fabric thatcontains non-elastic yarns and elastic yarns, and the warp knittedfabric more preferably contains non-elastic yarns in an amount of 85 to95 mass % and elastic yarns in an amount of 5 to 15 mass %, and evenmore preferably contains non-elastic yarns in an amount of 90 to 95 mass% and elastic yarns in an amount of 5 to 10 mass %. The warp knittedfabric is disposed such that the longitudinal direction of the elasticyarns (the longitudinal direction of the yarns) is along with the footwidth direction of the instep cover. The elastic yarns may be used asinserting yarns, or may be used as covering yarns for coveringnon-elastic yarns.

In one or more embodiments of the present invention, in light of thefact that it is possible to easily realize a structure in which theinstep cover is stretchable in the width direction of the foot, and thecenter portion of the instep cover located in the width direction issubstantially unstretchable in the length direction of the foot, thewarp knitted fabric that constitutes the tongue portion preferably has abasis weight (mass per unit area) of 300 g/m² or more, more preferablyhas a basis weight of 300 g/m² or more and 550 g/m² or less, and evenmore preferably has a basis weight of 300 g/m² or more and 410 g/m² orless.

In one or more embodiments of the present invention, the tongue portionpreferably continues to the tiptoe. This makes it possible to easilyrealize a structure in which the instep cover is stretchable in thewidth direction of the foot and the center portion of the instep coverlocated in the width direction is substantially unstretchable in thelength direction of the foot.

In one or more embodiments of the present invention, in light of thefact that it is possible to easily realize a structure in which thecenter portion of the instep cover located in the width direction issubstantially unstretchable in the length direction of the foot, theinstep cover main body is preferably constituted by a warp knittedfabric constituted by non-elastic yarns. Also, from the viewpoint ofweight reduction and air permeability, the warp knitted fabric thatconstitutes the instep cover main body preferably has a basis weight(mass per unit area) of 300 g/m² or more, more preferably has a basisweight of 300 g/m² or more and 550 g/m² or less, and even morepreferably has a basis weight of 300 g/m² or more and 410 g/m² or less.

In one or more embodiments of the present invention, a structure inwhich the instep cover is stretchable in the width direction of the footand at least the center portion of the instep cover located in the widthdirection is substantially unstretchable in the length direction of thefoot may be realized by providing a plurality of restricting portionsfor controlling extension in the length direction of the foot whileconstituting the foot cover main body and the tongue portion with use ofan elastic fabric.

In one or more embodiments of the present invention, different membersin the instep cover, such as the tongue portion and the instep covermain body, for example, may be formed as a single body through sewing.If different members are sewn together, in order to prevent damage toend portions and to prevent end portions from being frayed, and toenhance the aesthetic appearance, it is preferable to perform endtreatment by a hot-melt sheet (including a film) or the like. There isno particular limitation on the hot-melt sheet, and for example, it ispossible to use a polyurethane elastomer sheet as a hot-melt sheet.

In one or more embodiments of the present invention, it is preferablethat different members in the instep cover are joined together throughembroidery covering an end portion of at least one of the members. Ifthe tongue portion and the instep cover main body are constituted bydifferent materials, for example, it is preferable that the tongueportion and the instep cover main body are joined together throughembroidery covering an end portion of the tongue portion and/or theinstep cover main body. This realizes comfort contact with and goodfittability of a shoe to the instep side of the foot. A reinforcingnon-woven fabric is disposed on an embroidery portion, and thus joiningstrength is increased. There is no particular limitation on thereinforcing non-woven fabric, and a non-woven fabric that is usuallyused in embroidery may be used. The embroidery may be satin embroideryor tatami embroidery.

In one or more embodiments of the present invention, the upper mayfurther include a plantar cover for covering the entire plantar side ofthe foot. In this case, the upper has a bag shape having a wearingopening. This further increases the unity of the upper and the sole, andthus fittability is improved.

In a shoe of one or more embodiments of the present invention, the shoeupper and the sole are integrated. It is possible to obtain shoes thathave good fittability to the instep side of the foot and are capable ofinhibiting the depression of the heal at the time of coming into contactwith the ground. There is also no particular limitation on a method forintegrating the upper and the sole, and for example, the upper and thesole may be integrated with use of a usual cemented construction methodor the like, for example.

In one or more embodiments of the present invention, it is preferablethat a ground contact surface of the sole has a curved shape thatprotrudes downward in the forefoot portion, and, when, on the plantarcontact surface of the sole, a position of a rearmost end of a plantarcontact surface is the origin, a path length to a leading end of atiptoe that is measured along the plantar contact surface is L, and in astate in which a heel bottom surface of the plantar contact surface isdisposed in parallel to a horizontal plane, a sole thickness at aposition Sh where a path length from the position of the rearmost end ofthe plantar contact surface is 0.16×L is h, a sole thickness at aposition Sm2 where the path length is (0.3 to 0.5)×L is m2, a solethickness at a position Sm1 (where Sm1 is disposed frontward of Sm2)where the path length is (0.4 to 0.6)×L is m1, and a sole thickness at aposition Sf where the path length is 0.7×L is f, the followingrelational expressions (1) to (3) are satisfied,

m2≥m1  (1)

m1≥f,  (2) and

m1≥h,  (3) and

when an angle formed by a line that connects the position Sm1 and theposition Sh with a horizontal plane is θ1, a position where a verticalstraight line drawn from the position Sm1 intersects with a groundcontact surface of the sole is Sm1′, a position where a verticalstraight line drawn from the position Sh intersects with the groundcontact surface of the sole is Sh′, and an angle formed by a line thatconnects the position Sm1′ and the position Sh′ with a horizontal planeis θ2, θ2≥θ1 holds true.

In one or more embodiments of the present invention, it is preferablethat the sole thickness h at the position (that is, the center of theheel) Sh located 0.16×L from the origin is equal to or smaller than thesole thickness m1 at the position Sm1 located (0.4 to 0.6)×L from theorigin, and the angle θ2 formed by the line that connects the positionSm1′ and the position Sh′ with a horizontal plane is equal to or largerthan the angle θ1 formed by the line that connects the position Sm1 andthe position Sh with a horizontal plane. Accordingly, the heel does notcome into contact with the ground at the time of landing on the ground,and a heel strike does not occur, and thus it is possible to help theforefoot portion or midfoot portion to come into contact with the groundat the time of landing on the ground. Also, the sole thickness m2 at theposition Sm2 is equal to or larger than the sole thickness m1 at theposition Sm1, and accordingly, it is possible to keep the heel frombeing depressed downward due to the sole being inclined rearward whenthe sole comes into initial contact with the ground at the position Sm1′on the ground contact surface of the sole, and as a result, it ispossible to shift to forward rotation of the sole smoothly after theinitial ground contact. Also, the sole thickness fat the position (thatis, the center of the ball of the foot) Sf located 0.7×L from the originis equal to or smaller than the sole thickness m1 at the position Sm1,and the ground contact surface of the sole has a curved shape thatprotrudes downward at the forefoot portion. Accordingly, forwardrotation of the sole is smoothly performed. In this manner, the forefootstrike and the midfoot strike can be easily realized.

In one or more embodiments of the present invention, from the viewpointof further effectively inhibiting the depression of the heel after theinitial contact with the ground and further effectively facilitatingforward rotation of the sole, it is more preferable that m2 is largerthan m1, and m1 is larger than either h or f. In one or more embodimentsof the present invention, although not particularly limited, preferably,values such as those described below can be adopted as specific valuesof the sole thicknesses m1, m2, h, and f.

m1≥15 [mm]

m2≥16 [mm]

h≥10 [mm]

f≥10 [mm]

In one or more embodiments of the present invention, θ2+θ1 is preferably40 degrees or more, and more preferably 40 degrees or more and 55degrees or less. Accordingly, lifting effects are facilitated as aresult of the center portion of the instep cover substantially notstretching.

In one or more embodiments of the present invention, the sole thicknesst of the leading end of the tiptoe preferably satisfies t≤f/2.Accordingly, forward rotation of the sole can be smoothly performedtoward the leading end of the tiptoe.

In one or more embodiments of the present invention, the sole internallyhas a plate extending in the front-rear direction, and, a front end ofthe plate is disposed on the ground contact surface side of the forefootportion with respect to the center line of the sole thickness, a rearend of the plate is disposed on the plantar contact surface side of theheel portion with respect to the center line of the sole thickness, andthe center portion of the plate diagonally extends across the centerline of the sole thickness in the midfoot portion. Accordingly, when aload moves to the front end side of the plate after the initial contactwith the ground, the plate can reliably keep the heel from beingdepressed due to the sole being inclined rearward, and as a result, itis possible to more smoothly shift to forward rotation of the sole.

In one or more embodiments of the present invention, the plate has aportion protruding in the up-down direction, in at least a partialportion of the region extending from the position Sm2 to the positionSf. In this case, the flexural rigidity of the plate can be improved bythe protruding portion, and as a result, it is possible to furtherreliably keep the heel from being depressed after the initial contactwith the ground.

In one or more embodiments of the present invention, it is preferable toreinforce the tiptoe portion, the heel portion, and the eyelet portions(also referred to as shoelace passing portions) of the shoe with use ofartificial leather. The shape and holding properties of the shoe can bemaintained through reinforcement. Out of these portions, the heelportion is not necessarily reinforced if the weight of the shoe trulyneeds to be reduced. Also, the surface of the shoe upper may bedecorated as needed. In one or more embodiments of the presentinvention, the shoe may be provided with a shoelace.

In one or more embodiments of the present invention, although notparticularly limited, from the viewpoint of weight reduction, forexample, the mass per shoe is preferably 170 g or less, and morepreferably 90 g or more and 170 g or less.

Hereinafter, an embodiment of the present invention will be described indetail with reference to the drawings. The same reference numeralsindicate the same portions in the drawings. Note that the presentinvention is not limited to the embodiments shown in the followingdrawings.

FIGS. 1 to 10 illustrate a running shoe for middle and long distances,and an upper and a sole used in the running shoe. Note that it ispresumed that, in the description of the sole, upward (an upperside/upper) and downward (a lower side/lower) represent the positionalrelationship of the shoe in the up-down direction, and frontward (afront side/front) and rearward (a rear side/rear) represent thepositional relationship of the shoe in the front-rear direction, and thewidth direction indicates the right-left direction of the shoe. That is,if FIG. 9 is used as an example, upward and downward respectivelyindicate upward and downward in FIG. 9, and frontward and rearwardrespectively indicate leftward and rightward in FIG. 9, and the widthdirection indicates the depth direction on the page of FIG. 9.

FIG. 1 is a schematic spread-out surface view of an upper (a left shoe)of one embodiment of the present invention. FIG. 2 is a schematicsurface view of a shoe in which the same upper is used, FIG. 3 is aschematic back view of the same upper, and FIG. 4 is a schematicperspective view of the shoe in which the same upper is used. As shownin FIGS. 1 to 4, in this embodiment, an upper 1 includes an instep cover2 and a plantar cover 3.

In the instep cover 2, a tongue portion 4 and an instep cover main body5 are formed as a single body. This realizes comfort contact with andgood fittability to the foot, and good long-term wearability. The tongueportion 4 preferably continues to the tiptoe. This makes it possible toeasily realize a structure in which the instep cover 2 is stretchable inthe width direction of the foot and the center portion of the instepcover 2 located in the width direction is substantially unstretchable inthe length direction of the foot. In this embodiment, the width of thetongue portion 4 is gradually reduced from the ankle side toward thetiptoe. The tongue portion 4 may have the same width from the ankle sideto the tiptoe. The tongue portion 4 and the instep cover main body 5 arejoined together and formed as a single body through embroidery 6covering an end portion of the instep cover main body 5. This realizescomfort contact with and good fittability to the foot, and goodlong-term wearability. The inner instep cover 2 and the inner plantarcover 3 are constituted by single fabric, and the outer instep cover 2and the outer plantar cover 3 are constituted by single fabric. Theembroidery 6 may be satin embroidery or tatami embroidery.

The stretch of the upper 1 in the length direction of the foot and thewidth direction of the foot may be adjusted by providing a stretchcontrol portion 7 as appropriate. From the viewpoint of reinforcementand aesthetic appearance, the stretch control portion 7 may be providedthrough embroidery.

The instep cover 2 includes shoelace passing portions 10 and 11 throughwhich a shoelace 9 passes. The shoelace passing portion 10 may beprovided by partially integrating a lace or the like having apredetermined thickness with the instep cover main body 5 to constitutea shoelace passing portion having a predetermined size throughembroidery constituting the stretch control portion 7. The shoelacepassing portion 11 may be provided by performing embroidery around holesto form holes having a predetermined size in the tongue portion 4.

The inner plantar cover 3 and the outer plantar cover 3 are formed as asingle body through sewing 8, and the upper 1 has a bag shape having awearing opening 20. This further increases the unity of the upper andthe sole, and thus fittability is improved.

In a shoe 100, the upper 1 is integrated with a sole 500. The shoe 100includes a tiptoe reinforcing portion 12 and a heel counter 13. Thetiptoe reinforcing portion 12 may be constituted by artificial leather,for example. The heel counter 13 may be constituted by resin. The heelcounter 13 is provided with a lining material. The sole 500 will bedescribed later in detail.

The center portion of the instep cover 2 in the width direction of thefoot is substantially unstretchable in the length direction of the foot.Preferably, the instep cover 2 is stretchable in the width direction ofthe foot. Depression of the heel after the forefoot portion or themidfoot portion comes into contact with the ground during running isinhibited, and thus the foot is likely to move forward.

The tongue portion may be constituted by a single raschel fabric thatincludes elastic fibers (elastic yarns) in an amount of 5 to 15 mass %and non-elastic fibers (non-elastic yarns) in an amount of 85 to 95 mass%, that is disposed such that the longitudinal direction of the elasticfibers (elastic yarns) is along with the width direction of the foot,that has a basis weight of 300 g/m² or more and 550 g/m² or less, andthat has a thickness of 1 mm or more and 5 mm or less, for example.Spandex (monofilaments, 140 dtex) may be used as an elastic yarn, forexample. A polyester-based non-elastic yarn (multifilaments, the numberof filaments is 48, 150 dtex) may be used as a non-elastic yarn, forexample.

The instep cover main body and the plantar cover may be constituted by asingle raschel fabric that is constituted by non-elastic fibers(non-elastic yarns), has a basis weight of 300 g/m² or more and 550 g/m²or less, and has a thickness of 1 mm or more and 5 mm or less, forexample. A polyester-based non-elastic yarn (multifilaments, the numberof filaments is 48, 150 dtex) may be used as non-elastic fibers(non-elastic yarn), for example.

If the above-described fabric is used, adjustment is easily performedsuch that the tensile strength of the center portion of the instep coverlocated in the width direction when stretched by 10% in the lengthdirection of the foot is in a range of 50 to 70 N/mm². Also, adjustmentis easily performed such that the tensile strength of the instep coverwhen stretched by 10% in the width direction of the foot is in a rangeof 0.01 to 10 N/mm² while adjustment is performed such that the tensilestrength of the instep cover when stretched by 10% in the lengthdirection of the foot is in a range of 10 to 70 N/mm².

FIG. 5 is a schematic surface view of a shoe of another embodiment ofthe present invention. A shoe 200 of this embodiment has an upper 31. Inan instep cover 32 of the upper 31, a tongue portion 34 and an instepcover main body 35 are formed as a single body through sewing (notshown), and an end portion of the instep cover main body 35 is subjectedto end treatment by a hot-melt sheet 50 or the like. Shoelace passingportions 40 and 41 are constituted by providing holes having apredetermined size in portions that have been subjected to end treatmentby the hot-melt sheet 50. Portions other than the instep cover 32described above may have a configuration that is the same as that of theshoe 100. The shoe 200 includes a tiptoe reinforcing portion 42, a heelcounter 43, and a wearing opening 44, for example. Similarly to the shoe100, the upper 31 is integrated with a sole (not shown).

The center portion of the instep cover 32 in the width direction of thefoot is substantially unstretchable in the length direction of the foot.Preferably, the instep cover 32 is stretchable in the width direction ofthe foot. Depression of the heel after the forefoot portion or themidfoot portion comes into contact with the ground during running isinhibited, and thus the foot is likely to move forward.

FIG. 6 is a schematic spread-out front view of an upper of anotherembodiment of the present invention. An upper 61 of this embodimentincludes an instep cover 62 and a plantar cover 63. The instep cover 62and the plantar cover 63 are constituted by single fabric. A tongueportion 64 and an instep cover main body 65 are formed as a single bodydue to the instep cover 62 being constituted by single fabric. Thetongue portion 64 continues to the tiptoe. An stretch control portion 66is disposed in the center portion of the instep cover located in thewidth direction of the foot, the center portion corresponding to thetongue portion 64, such that the longitudinal direction thereof is alongwith the length direction of the foot, to perform control such that thecenter portion of the instep cover 65 in the width direction of the footis substantially unstretchable in the length direction of the foot. Fromthe viewpoint of reinforcement and aesthetic appearance, the stretchcontrol portion 66 may be provided through embroidery. FIG. 6 also showsa tiptoe reinforcing portion 72 and heel counters 73 and 74 that arejoined to the upper 61. Note that in the upper 61 of this embodiment,the tongue portion 64 and the instep cover main body 65 are notnecessarily and strictly distinguished from each other.

The center portion of the instep cover 62 in the width direction of thefoot is substantially unstretchable in the length direction of the foot.Preferably, the instep cover 62 is stretchable in the width direction ofthe foot. Depression of the heel after the forefoot portion or themidfoot portion comes into contact with the ground during running isinhibited, and thus the feet are likely to move forward.

FIG. 7 is a schematic spread-out surface view of an upper of anotherembodiment of the present invention, and FIG. 8 is a schematic surfaceview of a shoe in which the same upper is used. An upper 81 of thisembodiment includes an instep cover 82 and a plantar cover 83. Theinstep cover 82 and the plantar cover 83 are constituted by singlefabric. A tongue portion 84 and an instep cover main body 85 are formedas a single body due to the instep cover 82 being constituted by singlefabric. The tongue portion 84 continues to the tiptoe. A stretch controlportion 86 that has a fishing net shape is disposed on the upper 81 thatincludes the center portion of the instep cover located in the widthdirection of the foot, the center portion corresponding to the tongueportion 84, to perform control such that the instep cover 82 isstretchable in the width direction of the foot, whereas the instep cover82 is substantially unstretchable in the length direction of the foot.From the viewpoint of reinforcement and aesthetic appearance, thestretch control portion 86 may be provided through embroidery. In theupper 81 of this embodiment, the tongue portion 84 and the instep covermain body 85 are not necessarily and strictly distinguished from eachother.

A shoe 300 has a shoelace passing portion 90, and the shoelace passingportion 90 may be provided by partially integrating a lace or the likehaving a predetermined thickness with the instep cover 82 to constitutea shoelace passing portion having a predetermined size throughembroidery constituting the extension control portion 86. The shoe 300includes a tiptoe reinforcing portion 92, heel counters 93 and 94, and awearing opening 95. Similarly to the shoe 100, the upper 81 isintegrated with a sole (not shown).

The center portion of the instep cover 82 in the width direction of thefoot is substantially unstretchable in the length direction of the foot.Preferably, the instep cover 82 is stretchable in the width direction ofthe foot. Depression of the heel after the forefoot portion or themidfoot portion comes into contact with the ground during running isinhibited, and thus the feet are likely to move forward.

FIG. 9 is a schematic diagram illustrating a sole used in a shoe of oneor more embodiments of the present invention. The sole of thisembodiment may be used in the shoe 100 (the same applies to the shoes200 and 300). FIG. 9 is a longitudinal sectional view of the shoe 100shown in FIG. 4 taken along the center line of a sole 500 in thefront-rear direction, and here, for convenience of the illustration,hatching is omitted in FIG. 9, except for the upper and the outsole.Also, FIG. 9 shows a state in which a last (shoe last) 1000 is insertedinto the inner portion of the upper 1. A bottom surface of the last 1000is in contact with a plantar contact surface 501A of an upper midsole501 that constitutes the upper surface of the sole 500. Note that, ifthe shoe is provided with an insole, reference numeral 501A is notactually in contact with the plantar side of the foot, but referencenumeral 501A will be referred to as a plantar contact surface in thisspecification of this application, including this case.

As shown in FIG. 9, the sole 500 includes an upper midsole 501 disposedon an upper side, a lower midsole 502 disposed on a lower side, and anoutsole 503 that is mounted on a lower surface of the lower midsole 502and that has a ground contact surface 503B on the bottom surface sidethat comes into contact with the road surface.

The upper midsole 501 extends from a heel portion of the sole 500 to atiptoe portion in the front-rear direction. The lower midsole 502 isarranged mainly in a rearfoot region of the sole 500 (that is, a regionthat includes the heel portion and the midfoot portion), and is notprovided in the tiptoe portion of the forefoot portion.

It is preferable that a plate 504 is provided between the upper midsole501 and the lower midsole 502. It is preferable that the plate 504 is athin sheet-shaped member, and extends from the heel portion of the sole500 to the tiptoe portion in the front-rear direction. The plate 504 hasa thickness of about 1 to 2 mm, for example. The plate 504 is heldbetween a lower surface of the upper midsole 501 and an upper surface ofthe lower midsole 502 in the heel portion and the midfoot portion of thesole 500, and is held between the lower surface of the upper midsole 501and an upper surface of the outsole 503 in the forefoot portion of thesole 500.

It is preferable that the plate 504 has a protruding portion 510 thatprotrudes upward in a mountain shape in the midfoot portion of the sole500. The protruding portion 510 is recessed in a valley shape on theright and left sides, and forms a wave shape together with theprotruding portion 510. A ridge line and a valley line of this waveshape extend in the front-rear direction in the midfoot portion of thesole 500. The plate 504 may be formed in substantially a flat shape, inthe forefoot portion and the heel portion of the sole 500.

It is preferable that the upper midsole 501 and the lower midsole 502are constituted by soft elastic members. Although there is no particularlimitation on the soft elastic member, specific examples thereof includethermoplastic synthetic resins such as ethylene-vinyl acetate copolymers(EVAs), and foams thereof, thermosetting resins such as polyurethane(PU), and foams thereof, and rubber materials such as butadiene rubberand chloroprene rubber, and foams thereof. Although there is noparticular limitation of the plate 504, the plate 504 is preferablyconstituted by a thermoplastic resin such as a thermoplasticpolyurethane (TPU), a polyamide elastomer (PAE), or an ABS resin that isa relatively elastic material, or a thermosetting resin such as an epoxyresin or an unsaturated polyester resin, for example. Also, a fiberreinforced plastic (FRP) may be used as the material of the plate 504,for example. It is possible to use a fiber reinforced plastic in whichcarbon fibers, aramid fibers, glass fibers, or the like are used asreinforcing fibers, and a thermoplastic resin or a thermosetting resinis used as a matrix resin, as a fiber reinforced plastic, for example.It is preferable that the outsole 503 is constituted by a hard elasticmember. Although there is no particular limitation on the hard elasticmember, specific examples thereof include thermoplastic resins such asthermoplastic polyurethanes (TPUs) and polyamide elastomers (PAEs),thermosetting resins such as epoxy resins, and rubber.

As shown in FIG. 9, a ground contact surface of the sole, that is, theground contact surface 503B of the outsole 503 has a curved shape thatprotrudes downward in the forefoot portion.

When a position Se of the rearmost end of the plantar contact surface501A of the upper midsole 501 is the origin, and a path length(corresponding to a path length along the bottom surface of the last) toa position St of the leading end of the tiptoe that is measured alongthe plantar contact surface 501A is L, and, in a state in which theplantar contact surface of the heel portion (that is, a surfacecorresponding to the bottom surface of the heel) 501A is disposed inparallel to a horizontal plane Hp, the sole thickness at a position(that is, the position of the center of the heel) Sh located 0.16×L fromthe origin is h, the sole thickness at a position Sm2 located 0.3 to0.5×L from the origin is m2, the sole thickness at a position Sm1 (whereSm1 is disposed frontward of Sm2) located 0.4 to 0.6×L from the originis m1, and the sole thickness at a position (that is, the center of theball of the foot) Sf located 0.7×L from the origin is f, the followingrelational expressions (1) to (3) are satisfied.

m2≥m1  (1)

m1≥f  (2)

m1≥h  (3)

Because the sole 500 is constituted by the upper midsole 501, the lowermidsole 502, and the outsole 503, the sole thickness in each portionrefers to the total thickness of the sole that includes the uppermidsole 501, the lower midsole 502, and the outsole 503.

The position Sm1 corresponds to the initial ground contact position whenthe shoe lands on the ground during running when the forefoot portion orthe midfoot portion has landed on the ground. m2≥m1 in theabove-described inequality (1) means that the sole thickness on the rearside of the initial ground contact position is set to be at least equalto or larger than the sole thickness at the initial ground contactposition. This is for preventing the depression of the heel portion ofthe sole 500 after the initial ground contact. The sole thickness m2 atthe position Sm2 exerts a “supporting base” effect of supporting a loadat the position Sm2 after the initial ground contact at the positionSm1. Accordingly, when the sole 500 is about to fall in the heeldirection after the initial ground contact and the center of gravity isabout to move rearward, it is possible to shorten the time of movementof the center of gravity rearward as much as possible by restrictingsuch a movement of the center of gravity, and as a result, a load can besmoothly moved forward after the initial ground contact.

As a result of the above-described relational expression m1≥f(2) beingsatisfied, the center of gravity is likely to move forward after theinitial ground contact, facilitating forward rotation. As a result ofthe above-described relational expression m1≥h(3) being satisfied, it ispossible to facilitate the ground contact with the forefoot portion bypreventing the heel portion of the sole 500 from coming into contactwith the ground when the sole lands on the ground to make the heelportion float from the road surface.

Also, as shown in FIG. 9, it is preferable that, when the angle formedby a line that connects the position Sm1 and the position Sh with ahorizontal plane is θ1, a position where a vertical straight line drawnfrom the position Sm1 intersects with the ground contact surface of thesole is Sm1′, a position where a vertical straight line drawn from theposition Sh intersects with the ground contact surface of the sole isSh′, and the angle formed by a line that connects the position Sm1′ andthe position Sh′ with a horizontal plane is θ2, θ2≥θ1 holds true.Accordingly, it is possible to facilitate the ground contact with theforefoot portion by preventing the heel portion of the sole 500 fromcoming into contact with the ground when the sole lands on the ground tomake the heel portion float from the road surface.

In the forefoot portion of the sole 500, the ground contact surface 503Bhas a curved shape that protrudes downward (e.g., a smooth round shape).This can facilitate forward rotation after the initial ground contact.Also, a sole thickness t at a position St of the leading end of thetiptoe preferably satisfies t≤f/2. This can facilitate forward rotationtoward the leading end of the tiptoe after the initial ground contact.

As shown in FIG. 9, in the plate 504, a front end-side portion of theplate is disposed on the ground contact surface 503B side of theforefoot portion with respect to a sole thickness center line Sc, and arear end-side portion of the plate is disposed on the plantar contactsurface 501A side in a rearfoot region with respect to the solethickness center line Sc, and the center portion of the plate diagonallyextends across the sole thickness center line Sc in the midfoot portion.Note that, as shown in FIG. 9, the thickness center line Sc indicates aline that can be obtained by connecting centers of the sole 2 in thetotal thickness in the front-rear direction. Also, a protruding portion510 of the plate 504 is provided in at least a partial portion of aregion (that is, a region extending from 0.30 to 0.7 L from the origin)extending from the position Sm2 to the position Sf.

FIG. 10 is a schematic diagram illustrating the state of a shoe (a rightshoe) of one or more embodiments of the present invention worn duringrunning, showing movements of the shoe with respect to the road surfaceover time in the order of FIG. 10a to FIG. 10 d.

FIG. 10a shows the state of the shoe 100 immediately before the sole 500comes into contact with the ground, and an arrow F in FIG. 10a indicatesthe moving direction of the sole 500. At this time, as shown in FIG. 10a, the heel portion of the sole 500 floats from a road surface R, and thesole 500 is to come into contact with the road surface R at a portionhaving a thickness m1. This is because, as described above, m1≥h andθ2≥θ1 hold true in the sole 500, and thus when the shoe 100 lands on theground, the midfoot portion is likely to come into contact with theground, instead of the heel portion of the sole 500 coming into contactwith the ground.

FIG. 10b shows the state of the shoe 100 when initial ground contact ismade at a portion of the sole 500 having the thickness m1. At this time,as described above, m2≥m1 holds true in the sole 500, and the solethickness m2 on the rear side with respect to the initial ground contactposition is at least equal to or larger than the sole thickness m1 atthe initial ground contact position. Accordingly, movement of the heelportion of the sole 500 to be depressed downward immediately after theinitial ground contact is supported more by the position having thethickness m2 than by the portion having the thickness m1, and thus suchrearward movement can be restricted. As a result, when the sole 500 isabout to fall in the heel direction after the initial ground contact andthe center of gravity is about to move rearward, it is possible toshorten the time of movement of the center of gravity rearward as muchas possible, and thus, the weight of a wearer is likely to move forwardsmoothly after the initial ground contact.

FIG. 10c shows the state of the shoe 100 when the forefoot portion ofthe sole 500 comes into contact with the ground. At this time, asdescribed above, m1≥f holds true, and thus the weight is likely to moveforward after the initial ground contact, and thus forward rotation isfacilitated. Also, in this case, forward rotation after the initialground contact is facilitated due to the ground contact surface 503Bhaving a curved shape protruding downward. Also, in this case, when theweight moves toward the forefoot portion, the weight of a wearer can befirmly supported by the center portion and the heel portion of the plate504 due to the front end side portion of the plate 504 being pusheddownward, and it is possible to prevent the depression in the centerportion and the heel portion of the sole 500. As a result, the weight islikely to move toward the forefoot portion. Also, in this case, theflexural rigidity of the center portion is increased due to the centerportion of the plate 504 being provided with the protruding portion 510,and thus it is possible to further reliably prevent depression in themidfoot portion and the heel portion of the sole 500, as a result ofwhich the weight is likely to move toward the forefoot portion. Inparticular, the center portion of the instep cover 2 in the widthdirection of the foot in the upper 1 is substantially unstretchable inthe length direction of the foot, and thus the foot is lifted, thedepression of the heel portion is inhibited, and the foot is likely tomove forward.

FIG. 10d shows a kick-out phase with the tiptoe. At this time, becausethe sole thickness t at the position St of the leading end of the tiptoesatisfies t≤f/2, forward rotation toward the leading end of the tiptoeis facilitated. Also, in this case, because the midfoot portion and theheel portion of the foot are supported by the plate 504, at the time ofkicking out with the tiptoe, it is possible to obtain a propulsive forceby strongly kicking the road surface R due to the elastic repulsiveforce of the plate 504 being applied.

The above-described embodiments are to be considered in all respectsmerely as examples of the present invention and not limiting. Personsskilled in the art relating to the present invention may constructvarious embodiments employing the principles of the present invention,without departing from the spirit and essential characteristics of thepresent invention when considering the above-described teaching, even ifnot explicitly stated in this specification.

An upper of one or more embodiments of the present invention can besuitably used as an upper of a sports shoe, specifically, an upper of arunning shoe, in particular, an upper of a running shoe for middle andlong distances. Also, a shoe of one or more embodiments of the presentinvention can be suitably used as a sports shoe, specifically, a runningshoe, in particular, a running shoe for middle and long distances.

The invention may be embodied in other forms without departing from thespirit or essential characteristics thereof. The embodiments disclosedin this application are to be considered in all respects as illustrativeand not limiting. The scope of the invention is indicated by theappended claims rather than by the foregoing description, and allchanges which come within the meaning and range of equivalency of theclaims are intended to be embraced therein.

What is claimed is:
 1. A shoe upper, the upper comprising: an instepcover for covering an instep side of a foot, wherein the instep coverhas a structure in which a tongue portion and an instep cover main bodyare formed as a single body, and a center portion of the instep coverlocated in a width direction is substantially unstretchable in a lengthdirection of the foot.
 2. The shoe upper according to claim 1, wherein atensile strength of the center portion of the instep cover located in awidth direction when stretched by 10% is 50 N/mm² or more.
 3. The shoeupper according to claim 1, wherein the instep cover is stretchable in awidth direction of the foot.
 4. The shoe upper according to claim 1,wherein the tongue portion continues to a tip of a toe.
 5. The shoeupper according to claim 1, wherein the tongue portion is constituted bya warp knitted fabric that includes a non-elastic yarn and an elasticyarn.
 6. The shoe upper according to claim 1, wherein different membersin the instep cover are joined together through embroidery covering anend portion of at least one of the members.
 7. The shoe upper accordingto claim 1 wherein the upper further comprises a plantar cover forcovering the entire plantar side of the foot.
 8. The shoe upperaccording to claim 2, wherein the instep cover is stretchable in a widthdirection of the foot.
 9. The shoe upper according to claim 2, whereinthe tongue portion continues to a tip of a toe.
 10. The shoe upperaccording to claim 2, wherein the tongue portion is constituted by awarp knitted fabric that includes a non-elastic yarn and an elasticyarn.
 11. The shoe upper according to claim 2, wherein different membersin the instep cover are joined together through embroidery covering anend portion of at least one of the members.
 12. A shoe, the shoecomprising: a shoe upper and a sole, wherein the upper comprises aninstep cover for covering an instep side of a foot, the instep cover hasa structure in which a tongue portion and an instep cover main body areformed as a single body, and a center portion of the instep coverlocated in a width direction is substantially unstretchable in a lengthdirection of the foot, and wherein the shoe upper is integrated with thesole.
 13. The shoe according to claim 12, wherein a tensile strength ofthe center portion of the instep cover located in a width direction whenstretched by 10% is 50 N/mm² or more.
 14. The shoe according to claim12, wherein the instep cover is stretchable in a width direction of thefoot.
 15. The shoe according to claim 12, wherein the tongue portioncontinues to a tip of a toe.
 16. The shoe according to claim 12, whereinthe tongue portion is constituted by a warp knitted fabric that includesa non-elastic yarn and an elastic yarn.
 17. The shoe according to claim12, wherein different members in the instep cover are joined togetherthrough embroidery covering an end portion of at least one of themembers.
 18. The shoe according to claim 12, wherein the upper furthercomprises a plantar cover for covering the entire plantar side of thefoot.
 19. The shoe according to claim 12, wherein a ground contactsurface of the sole has a curved shape that protrudes downward at aforefoot portion, and, when, on a plantar contact surface of the sole, aposition of a rearmost end of the plantar contact surface is the origin,a path length to a leading end of a tiptoe that is measured along theplantar contact surface is L, and in a state in which a heel bottomsurface of the plantar contact surface is disposed in parallel to ahorizontal plane, a sole thickness at a position Sh where a path lengthfrom the position of the rearmost end of the plantar contact surface is0.16×L is h, a sole thickness at a position Sm2 where the path length is(0.3 to 0.5)×L is m2, a sole thickness at a position Sm1 (where Sm1 isdisposed frontward of Sm2) where the path length is (0.4 to 0.6)×L ism1, and a sole thickness at a position Sf where the path length is 0.7×Lis f, the following relational expressions (1) to (3) are satisfied,m2≥m1  (1)m1≥f,  (2) andm1≥h,  (3) and when an angle formed by a line that connects the positionSm1 and the position Sh with a horizontal plane is θ1, a position wherea vertical straight line drawn from the position Sm1 intersects with theground contact surface of the sole is Sm1′, a position where a verticalstraight line drawn from the position Sh intersects with the groundcontact surface of the sole is Sh′, and an angle formed by a line thatconnects the position Sm1′ and the position Sh′ with a horizontal planeis θ2, θ2≥θ1 holds true.
 20. The shoe according to claim 19, wherein thesum of the θ2 and the θ1 is 40 degrees or more.